1. Field of the Invention
This invention relates to roof edge seal and barrier devices and their manufacture.
2. Discussion of Background Information
There are a very wide variety of roof constructions, which generally consist of a supporting structure on to which roofing materials are laid in a fashion which provides a waterproof seal so that when rain falls on the roof, it runs off rather than penetrating into the building concerned. Inside the roof, it is desirable that the roof space is not sealed but rather ventilated.
Problems arise in connection with providing a structure at the edge of the roof where it overlies the walls of the building below it, and which resists water penetration but which still allows the roof space to “breathe”. This may be achieved in a variety of traditional ways, and is generally relatively easily achieved when the underside of the roofing material is relatively flat. In the case of roofing materials which do not have a flat underside, for example corrugated sheeting or non-flat tiles, it is generally necessary to provide some sort of structure or material to fill in the gaps. This is laborious to achieve by individually filling each gap e.g. with a settable mortar or like material, and a wide variety of sealing strips have been developed. The purpose of such strips is not merely to generally seal the gaps, but to ensure that they are sealed adequately not only against the ingress of water, but against wildlife, for example small birds who may wish to nest in the roof, bats, rodents and a wide variety of flying insects. It would be desirable for the seal to work to prevent the ingress of non-flying creatures, such as slugs, snails and spiders, though, in the case of the last of these, small spiders will inevitably be able to get into a roof space via very small passages at the edges where the roof sits on the wall.
Particularly for use with corrugated tiles or corrugated sheet roofs, a number of proposals have been made. U.S. Pat. No. 6,243,995 and 2003/0005649 disclose systems for fitting under curved roof tiles at the edge of a roof while Specifications EP 0084909, NL 1002170, FR 2539787 and published Australian Applications 39621/78 and 2008101266 disclose a variety of strips including a comb-like formation where the individual teeth may be flexed or bent to provide a set of adjacent bars which constitute a barrier to entry of undesired wildlife between corrugated sheeting or tiles and a flat base constituted by the top of a wall. An advantage of such a system is that strips may be fixed in place with the teeth protruding at an appropriate angle and then, as the roofing components are laid, the underside of each component bends the teeth so that they conform to the shape of the underside of the roofing material and constitute an appropriate barrier.
Such comb-like seal strips are conventionally produced of metal by stamping the teeth out from a metal strip. This is a process which gives rise to substantial quantities of stampings which, while they might be recyclable, are often simply disposed of as waste.
For clarity, any prior art referred to herein, does not constitute an admission that the prior art forms part of the common general knowledge, in Australia or elsewhere.